The following description relates to a synchronous engagement clutch and, more specifically, to a ball retention assembly for a synchronous engagement clutch.
An air turbine starter (ATS) is an engine accessory which drives an internal combustion engine to a required speed prior to ignition during start up. The ATS is driven with pressurized air regulated by a starter air valve (SAV). Pressurized air, usually delivered from an auxiliary power unit (APU), cross-bleed from a running engine or an external air cart is directed into the turbine blades to cause the rotor to rotate. This interacts with a gear reduction stage and clutch component, which then delivers mechanical power to the accessory gearbox. Rotation from the gearbox in turn rotates the high pressure (HP) engine rotor assembly to induce airflow through the engine and consequently causes the rotation of the low pressure (LP) rotor. Once the engine has reached a determined cut-off speed, the starter control valve (SCV) cuts off air flow and the starter disengages the drive train through the action of its clutch.